1 #include <windows>
 2 int main(int argc, char* argv[])
 3 {
 4       HKEY hKey;
 5       DWORD dwType = REG_SZ;
 6       DWORD dwSize = 255;//须指定长度,否则第一次读取RegQueryValueEx不成功，仅返回长度
 7       char data[MAX_PATH];
 8       bool ret;
 9 
10 
11       if(RegOpenKey(HKEY_LOCAL_MACHINE, "SOFTWARE\\Microsoft\\Windows NT\\CurrentVersion", &hKey) == ERROR_SUCCESS)
12         cout << "open success" <<endl;
13 
14       ret = RegQueryValueEx(hKey,"ProductName",
15                       NULL,
16                       &dwType,
17                       (LPBYTE)data,
18                        &dwSize) == ERROR_SUCCESS;
19 
20       RegCloseKey(hKey);
21       //ret = wcscmp(data, L"Microsoft Windows XP") == 0;
22       cout << data << endl;
23 
24       system("pause");
25 
26      return 0;
27 }